Is there totally not a man alive who doesn't dream of settling down with a young thing at 55 and popping out a kid or two, enjoying a few years with them, and then settling into the grandpa role while his young wife does the hard lifting? Hm. Maybe I am describing my own experience with men -- at least the ones here in New York. Look at any online dating site and marvel at the amount of men 45, 55, even 65, who advertise their desire to "definitely" have kids -- "someday"! Well, of course, they think this is perfectly reasonable. It's the women who run out of eggs -- the men who still have sperm until their last breathing day, right? Well, they might have sperm. But according to a new study, it's "mutant sperm!" Bwahaha! Run, run, from the mutant sperm!

Researchers have already warned men who wait too long to have children highly increase the risk that their children will have an array of health and development issues, including Alzheimer's disease, bipolar disorder, heart disease, birth defects and cancer.

But now here comes a new study sure to send shivers down the biological clock of offspring-minded men -- men in their 40s are apparently twice as likely to pass down genetic mutations to their kids than men in their 20s.

On the other hand, older mothers had no bearing on whether kids got genetic mutations, since 97 percent of all mutant DNA comes from dads. Who knew??!!

Genetic mutations can lead to disorders such as autism and schizophreniaand even rare ones such as the bone disorder Apert syndrome. Indeed researchers are beginning to believe that the explosion of autism is due to guys having kids so late now.

What's my point in this? It's to get guys to stop pussyfooting around! Not every guy has to have kids, of course, but if you know you want them, you need to think about your biological clock as much as women.

Guys, if you are 38 and think you want kids, why wait until you are 45, just so you can get in a few more years of sewing your wild oats? Is it really worth the risk?

These types of studies have been out there for awhile, so I'd be surprised if it has much effect on men's dating and mating habits -- but perhaps the term "mutant sperm" will stick in men's heads. Mutant sperm, guys! It's green and glowing and has three heads!

Stop dilly-dallying and give that woman you've been dating for eight years a ring already, will ya?!